The term prototype does not always indicate mistakes. It, to me, stands for a first example of a new design. Some changes might occur in the design within the next consecutive pieces but that doesn't mean mistakes were involved in the first one.
I think some prototypes are worth the money but it depends on who made it. Was there a prototype for the Moran ST-24? Obviously there was a first one made. That one is probably more valuable than a new one.
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If a man can keep alert and imaginative, an error is a possibility, a chance at something new; to him, wandering and wondering are a part of the same process. He is most mistaken, most in error, whenever he quits exploring.
William Least Heat Moon
[This message has been edited by Phillip Jones (edited 14 December 1999).]